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Network Files

Network files (specified by the -F command line parameter) contain the representation learned by SNoW for each of the target nodes as well as all the information required for SNoW to recreate (in testing) the structure learned during training. Each target node has a section in the file containing information on its algorithm's parameters and features (most notably, the features' weights). The header line for each target node takes the following form:

target ID priorProbability cloudConfidence activeCount nonActiveCount algorithm
learnerType parameters

For example:

target 2 0.4 0.473593433165 42 63 winnow 1 1.35 0.8 4 0.2

This specifies a target node with ID $ 2$, prior probability $ 0.4$ (the fraction of training examples labeled with the target ID), and cloud confidence $ 0.4736$ (see Section 4.3.5), which appeared active in $ 42$ examples, and was not found active in $ 63$ examples. It uses the Winnow algorithm found at index $ 1$ of an internal data structure that maintains information on every algorithm used by the network and their parameters. The Winnow algorithm used by this target node has an $ \alpha $ of $ 1.35$, a $ \beta $ of $ 0.8$, a threshold of $ 4$, and a default feature weight of $ 0.2$.

Following the target node header, the target node's features are enumerated. Each line corresponds to a single feature, in the format:

ID : learnerType : featureID : activeCount updates weight

For example:

1 : 2 : 34 : 13 6 0.3645

This specifies a feature which is linked to target node $ 1$ using algorithm $ 2$, and its ID is $ 34$. It had an active count of $ 13$, and its weight was updated $ 6$ times during training. After those $ 6$ updates, its weight is now $ 0.3645$.

For those users who are concerned about a feature with very large ID found in their network files, take a look at the -f command line parameter.



Next: Error Files Up: File Formats Previous: Example Contents
Cognitive Computations 2004-08-20